Arrangement for drawing fuel out of the induction conduit of internal combustion engines



May 14, 1940. SCHEERER 2,201,014

ARRANGEMENT FOR DRAWING FUEL OUT OF THE INDUCTI ON CONDUIT OF INTERNAL COMBUSTION ENGINES Filed June 8, 1938 7/71/61] far.-

PATENT @FFICE ABBANGEhfENT roa naswma our OF THE INDUCTION OONDUIT O! IN- I TEBNAL COMBUSTION ENGINES Georg Scheerer, smmre-m-csmi u,

Ger-

many, asslgnor to Daimler-Benz Akt engesellschaft, .Stnttgart-Untertnrkheim, Germany Application June 8, 1938, Serial No. 212,525- In" Germany June 9, 1937 dclaims.

This invention relates to an arrangement'for drawing fuel out of the induction conduit of internal combustion engines with charging blower, and it has forits object to prevent the sparking 5 plugs from becoming wet and consequently the operation of the engine being disturbed by excess fuel during service, especially under light load and when running idle.

In internal combustion engines with charging blower, in which the charging blower is arranged between the carburettor and the engine cylin- P ders, the induction conduit is chosen with ver large cross-sectional area so that, in spite of the large quantities of mixture delivered by the charging blower, the speed in the induction conduit can be kept low. These large induction conduits are, however, open to the objection that, especially under light load and when running idle, relatively large quantities-of fuel deposit in the conduit and-the sparking plugs become wet. The result of this is, that sparking trouble occurs and'the operation of the engine becomes; irregular or even interrupted entirely.

These objections are. overconie according to the invention in that in the induction conduit catching devices of any shape are arranged from v which the deposited excess fuel is sucked. The catching devices are devices outside from the cross-section of the conduit and branch of! from the conduit at the bottom of the latter. The fuel collected in the catching devices may be either drawn of! by the superpressure in the conduitor by the suction of the charging blower or by a separate-pump. The catching devices which may be constructedfor example as pocket-like depressions, are'all connected by a common conduit communicating with the suction chamber of the charging blower or the pump, .Preferably the catching devices are provided at spots of the conduit where whirls occur.

As experience has shown that the greatest quantity of fuel deposits andcollects on the cylinders situatedfarthest towards the rear and this impairs the operation of the sparking plugs. I the end of the induction conduit, 1. e., the part of the conduit which has the greatest distance from the carburettor, is constructed as a separate collecting trap from which the depdsited fuel is sucked in the same manner as from ,the o catching pockets. The separate collecting trapis preferably provided at the, bottom ,of the conduit.

An embodiment of the invention is illustrated diagrammatically in the accompanying drawing. The fuel-air mixture sis fed to the cylinders a by the charging blower I through the main induction conduit 12 and the branch conduits c. 1 me air sucked in through the pipe 1 takes up fuel at the throttle point i fromthe nozzle k i the induction conduit -b for catching the fuel,

which said end depression is of a greater depth (oi. res-119) connected with the float chamber 111. The fuelair mixture is sucked through theadjustable throttle valve 0 and conduit h by the charging blower f and forced into the induction conduit 11 whence it is fed to the cylinders a. when theengine is running under light load or idle, the

excess fuel flows oi! on the walls of the induction conduit 1; and collects inthe pocket-like de.-- pressions 11 arranged at the lowest points. From these depressions the fuel is sucked by the charging blower I through the conduit e andag'aih mixes with the charge mixture. At the end of the induction conduit b a separate trap n is arranged from which the collected excess .fuel is also drawn off-through the conduit e by the suctlon action of the charging blower I.

Also separate catching plates or similar elements may be provided in the lower portion of instead of the catching devices in the -form of pocket-like depressions d illustrated.-

Having now particularly described and ascer tained the. nature of my said invention and in what. manner the same is tobe performed. I declare that what I claim is: a

'1. In a combustion engine, the combination with a carburetor, an intake manifold of relatively wide cross-section and a charging blower between said carburetor and said manifold, of catchin devices for the, fuel condensate disposed in said manifold, one of said catching devices being disposed at the end of said manifold remote from said charging blower. 2. m a' combustion engine, the combination with a carburetor,'an intake manifold of rela-' -tiveiy wide cross-section and a charging blower between said carburetor and said manifold of fuel condensate catching depressions provided at the bottom of said manifold, and acommonpipe connecting the lower ends of all said de- 40 pressions and leading toythe'suction side of said blower, one of said depressions. being'disposcd, at the end of said manifold remote from said blower.

3. An arrangement, as claimed in claim 2, in than the rest of the depressions.

-' 4. In a multi-cylinder combustion engine, the

' site saidbranch conduits. respectively, and an s,

additional fuel condensate catching depressions 66 at the end of said manifold remote from said blower.

,GEORG 

